lang1-parser.cljc

(def lang1-parser
  (instaparse.core/parser
   "prog = (spaces? expr spaces? <';'> spaces?)*
      <expr> = assig | add-sub
      assig = varname spaces? <'='> spaces? expr
      <add-sub> = mult-div | add | sub
      add = add-sub spaces? <'+'> spaces? mult-div
      sub = add-sub spaces? <'-'> spaces? mult-div
      <mult-div> = factor | mult |div
      mult = mult-div spaces? <'*'> spaces? factor
      div = mult-div spaces? <'/'> spaces? factor
      <factor> = number | <'('> spaces? expr spaces? <')'> | varget |assig
      <spaces> = <#'\\s+'>
      number = #'-?[0-9]+'
      varget = varname | argument
      varname = #'[a-zA-Z]\\w*'
      argument= <'%'>#'[0-9]+'"))